As display screens are developing constantly, consumers require higher and higher stability of display screens. The stability of display screens highly depends on their gate driving circuits, and shift register elements constituting the gate driving circuits.
At present, a shift register element in which a control signal is a scan signal is illustrated in FIG. 1A, which shows a schematic structural diagram of a shift register element in the prior art including six transistors (M1 to M6) and two capacitors (C1 and C2), where all of the first transistor M1 to the sixth transistor M6 are P-type thin film transistors. FIG. 1B illustrates a timing diagram corresponding to the circuit of the shift register element illustrated in FIG. 1A, where in a T stage, the fourth transistor M4 is switched on by a first scan signal S1 to provide a first node N1 with a low-level signal, and the fifth transistor M5 is switched on to provide a second node N2 with a high-level signal; in a T2 stage, potentials of both the first node N1 and the second node N2 are maintained by capacitors; in a T3 stage, the sixth transistor and the third transistor are switched on by the second scan signal S2 to provide the second node N2 with a low-level signal, and the first node N1 with a high-level signal; and in a T4 stage, the first node N1 and the second node N2 are not provided with any signal but are floating until the end of a frame, where their potentials are maintained by the capacitors, so there is poor stability of the circuit because the first node N1 and the second node N2 are susceptible to interference of an external signal, e.g., an electrostatic signal, a scan signal or an output signal of another level of circuit, etc., thus easily resulting in an output error of the circuit.